Telephone-exchange system.



C. L. GOODRUM. TELEPHONE E'XCHANGE SYSTEM- APPLICATION FAILED .DEC.30, 91s.

Patented Jan. 15, 1918.

Wye/160R. Char/es LGoodrum systems containing a CHARLES L. GOODBUM, OF.NEW YORK, N. Y., ASSIGNO OF NEW YORK, N. Y A

PANY, INCORPORATED,

TO WESTERN ELECTRIC COM- RPORATION OF NEW YORK.

TELEPHONE-EXCHANGE sYs'rn /r.

To all whom it may concern:

Be it, known that I, CuAnLss L. GooonUM, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and-useful Improvements in Telephone- Exehange Systems, of which the following is a full, clear, concise, and exact description.

This invention relates to machine switching telephone exchange systems with subscribers control, and more particularly to large number of oilic'es. Experience has demonstrated that subscrib ers have difficulty in building up connections involving more than five digits.

The object of this invention is to' enable a. calling party to establish a connection with any other party in a large system without the necessity of remembering a large number of digits while operating his finger 'wheel.

In accordance with this invention, each calling line is provided with a number of in ual devices, such as keys, for selecting an actuating one of a number of nonnumerical switches at the ofiice in which such line terminates to extend the line to one oi the connecting circuits of' the group leading to the desired group of called lines. This connecting circuitterminates ma first selector. This selector and succeeding selectors and a connector are then set by the calling'party operating his finger wheel in the welhkhown manner. The calling party thus'niakes a preliminary first division, for example, the district, by a key, independently. of the finger wheel, and then in'operat-ing his finger wheel to select the office, thousands, hundreds, tens and units digits oi the called line, need only remember five numbers or characters.

More specifically, each line terminates in a number of line switches each having access to a group oi: connecting circuits leading to adiflerent line group, and each callin line is rovided with a line relay for eacli line switch and with manual keys at the calling substation, for closing circuits to selectively operate said line relays to actuatethe corres onding line switch. The calling party t ien' operates his finger wheel to set the re maining numerical switches.

Referring to. the drawing, which shpws only so much of a telephone exchange sysspeciflcation of Letters Patent.

P'atented J an. 15, 1918.

Application filed December 30, 1916. Serial No. 139,802.

term as is necessary for a comprehension of the invention, lines 1 and 2 terminate in: brushes 3 and i of line switch A, and also inbrushes 5 and 6 of line switch B at the central office. This line switch may be of the type shown in United States Patent No. 1,203,166. The calling line is also provided with a line relay 7 for controlling line switch A, and a line relay 8 for controlling line switch B, and with a common cut-off relay 9, which, when operated, removes the control of both of these line relays from the calling line. The group of line switches to which switch A belongs is controlled by a master switch 10, and the group of line switches to which switch 13 belongs, by a master switch 11. These master switches are shown and described in the patent to which reference has been made. The function of the master switch is to keep the brushes 3, 4, 12, 13 and 1:4 pointed toward an idle trunk. \Vhen a; call comes in, the relay 56 operates and causes such brushes to engage the corresponding fixed terminals 15, 16, 17, 18, 19, thus seizing such trunk. The master switch then causes the brushes of the remainin line switches to be moved into operative re ation to the next idle trunk.

The invention will be more readily understood from a detailed description of the operation of the system. The party at substation G, desiring to make a call, depresses one of the keys 20, 211 depending upon the district in which the desired line is located.

The depression of key; 21', assuming th selection of the called line to be in the district corresponding to this key, results in the closure of the fol lowing circuit: ground, key- 21, conductors l. 22, E23, inner armature and'back Contact of the cut-off relay 9, line relay 7. of line switch A to free pole of battery. Relay 7, in attracting its armature, closes circuit for magnet 56, from ground, arms: ture and front contact of re ing of magnet 56, conductoture and back contact of loc ring magnet 28 of the master SWlL 29, permits the brushes 3, 4, 12, 13 and 14 to engage the terminals 15, 16, 17 18 and 19. The en agement of brushes 3 and 4 with 'termina s 15 and 1 6 energizes the stepping relay of the selector in which conductors 24, 25 "and 26 terminate, which selector has access to groups of trunks leading to oflices in 'h 10, to free pole otbat 'tery. Magnet 56, in attracting its armature the following lay 7, left wind- 27, left armaT- roe the selected district. This relay, inoperating, causes a ound to be placed upon test wire 26, as in y'shown and described in the above mentioned patent. The right winding of magnet 56 being now connected by brush 13 to said grounded conductor, the magnet maintains its armature attracted after the original energizing circuit throu h the left-hand winding is opened. This c1rcuit is now opened b the deiinergization of relay 7, following the energizatlon of the cut-oif rela 9 from free pole of battery, winding 0 relay 9, brush 12, to ground. The line relay 7 is constructed so as to be slow to release to prevent the opening of the circuit through the left winding of relay 56 before the circuit is closed through therlght winding of said relay, The magnet 56 may also be made slow.

The engagement of brush 14 with terminal l9 grounds the contact 'on the master switch contact bank corresponding to the connecting circuit just seized, and causes relay 30 of,

the energization of: the startin the master switch 10, which, 1n operating, causes the master switchto advance the remaining plungers into operative relation with the next idle trunk. More in detail, the relay 30, in attracting its armature,

closes the following circuit for the locking magnet 28: free pole of battery, magnet 28, armature'and front contact of relay 30, right winding of supervisory relay- 31 to ground. Magnet 28, in attracting its left armature, disconnects battery from the magnets 56 of the remainin li'ne switches controlled. by master switc 10, to prevent such line switches from being operated while the master switch 10 is moving. The attraction of the armature of relay 30 also causes the closure of a circuit for the tri magnet 32 if the arm'33 is in the POSI- tion shown, which is its end position. In this event the following'circuit is closed due to the closure of contact 34: free pole of battery, magnet 32, contact 34, armature and front contact of relay 30, right winding of relay 31 to ground. The magnet 32, in attracting itsarmature, closes a circuit for the solenoid 35 of the master switch 10 to move the brushes of the remaining line switches into operative relation with trunk Although the circuit of the trip magnet 32 is broken as the arm 33 in the first part of its movement opens contact 34, due to the armature of said magnet bein locked by the catch 36, the circuit for sue solenoid. .is maintained until such arm reaches its extreme position when it releases the armature and breaks the solenoid circuit.

The calling line having thus been extended to an oiiiceselector, the calling party nowremoves his receiver and operates his finger wheel S to set'the brushes 37*, 38 "39 of the ofice selector into operative relation with 1,203,166. 'on' the other hand 'that thevThe brushes 60, 61 of the connector are then set upon the multiples 62, 63 of the-desired line.. The selectors and trunk circuits are only diagrammatically shown, since they are wel known in the art. They may be of the type, for example, shown in Patent No.

Assuming called line 1s located another district. Instead of depressin the key 21, the key 20 would be depressuf by the callin party, resulting in the closure of the fol owingcircuit for line relay 8 of line switch B, ground,

key 20, conductors 1, 47, 48, outer armature and back contact of relay 9, line relay 8,

free pole of battery. Relay 8, in attracting its armature, closes a circuit to operate magnet -4 9 of the line switch B,- w ich, in attractmg its armature 50, causes the seizure 'of the trunks 54, 5'1, 57, terminating in brushes 52, 53, 58- of a selectorhavingaccess to the oflices in. this district. .From this point on the operation is the same as that already traced forthe line switch A.

What is claimed is: 1. In a telephone exchange system, the combination with calling and called telephone lines, a numerical switc es for said'calling line, connecting circuits leadin from said switches in the direction of ifiereiit called, line groups,-and manually operable devices associated with the calllng line for selectively operating said switches to extend such calling line to a connecting circuit leading to the desired called line group.

2. In a telephone exchange system, the combination with calling and called telephone lines, aplurality of automatic nonnumerical switches forf said calling line, connecting circuits 1 fromsaid switches in the directio line groups, said circuits terminating in 'auto'entend such line to a connecting circuit leading to the des red called line group, other automatic numerical'switches, and a sender associated with the calling line for setting said numerical switches to intercone calling and calledlines.

nect t 3, In a te ephone exchange system, the combination with calling and called telephone lines, a. plurality of line switches for lurality of automatic nondin of different called manually operable devices associated with the callin line for selectively operating its lineswitc es to seize a trunk of the corresponding group.

4. In a-telephone exchange system, the

combination with calling, and called telephone lines, a plurality of line switches for each calling line, a group of connectin circuits leading from each switch in the weetion of different called line groups, said circuits terminatin in automatic numerical switches, manually operable devices associated with the callin line for selectlvel' operating its line switch to seize a trun the corresponding group, other automatic numerical switches, and a sender associated with the calling line for setting said numerical switches to interconnect the calling and called lines.

, 5. In a" telephone exchange system, the combination with called telephone lines divided into groups, groups of connecting circuits each leading in the direction of a different line group, a group of non-numerical switches for each group of connecting circuits, a calling line, means controlled by the calling party for operating a non-numerical switch of any group to extend the callin line to one of the connecting circuits of she group, and means for extending the calling line over said connecting circuit in the direction of the called line.

6. In a telephone exchange system, the combination with called telephone lines divided into groups, groups of connecting circuits each leading in the direction of a different line group, a calling line, a non-numerical, switch therefor for each group of connecting circuits, an electromagnetic responsive device for each switch for causing suchswitch to operate to extend the calling line to a connecting circuit of the group with which said switch is associated, and manual means associated with the calling line for selectively operating said electromagnetic responsive devices.

, 7. In a telephone exchange system, the combination with called telephone lines di- "vided into groups, groups of connecting cirirec cuits each leading in the direction of a different line group, a callingline, a non-numerical switch therefor for each group of connectin circuits, an electromagnetic responsive device for each switch for causing such switch to operate to extend the calling line to a connecting circuit of the group with which said switch is associated, a manual key for each electromagnetic responsive device, and a circuit including one ,of said keys andv the correspondingh device and adapted when closed to operate t e same to cause the corresponding switch to extend the calling line to one of the connecting circuits ofthe desired group.

8. In a telephone exchan e system,the comv bination with called telep one lines divided into groups, groups of connecting circuits each leading in the direction of a different line group, a calling line, a non-numerical switch therefor for each group of connecting circuits to extend such line to said connecting circuits, 3. line relay associated with each calling line for each switch, means controlled by the calling party for selectively operating said line relays, and means controlled by a line relay when operated to cause the associated switch to extend the callin line to a connecting circuit of the desire group.

9. In a telephone exchange system, the combination with telephone lines divided into groups, called terminals therefor, groups of connecting circuits each leading in the direction of a different line group, a group of non-numerical switches for each group of connecting circuits for extending calling lines to sai connecting circuits, at line relay associated with each calling line for each switch, means controlled by the calling party for selectively operating said line relays, means controlled by aline rela when operated to cause theii'ssociated switc to extend the calling line qt/O a connecting circuit of the desired group, and a common cutoff relay operated when said line has been extended to disconnect all of said line relays from the calling line.

In witness whereof, I hereunto'subscribe my name this 29th day of December, A. D.,

C ARLES n. eooinRUM. 

